1. Field
Exemplary embodiments of the present invention relate to a transparent display device using a bistable mode of a cholesteric liquid crystal as a drive mode of a reflector, and a driving method of the transparent display device.
2. Discussion of the Background
Flat panel display technology started with the development of liquid crystal display (LCD). With the marvelous advances in technology, flat panel display technology has been applied to most display fields ranging from small-sized mobile devices to notebook computers, monitors, televisions (TVs), and other large-sized display devices. In recent years, transparent display devices are increasingly becoming attractive because they can display information and background at the same time.
A transparent display device includes a high-transmittance screen to make a back surface of the screen visible. Generally, a transparent display device includes a backlight unit, a light guide plate, a liquid crystal panel, and a color filter. Technologies for transparent display devices are disclosed in Korean Patent Registration No. 10-0962109 entitled “REFLECTIVE PLATE, BACKLIGHT UNIT AND LIQUID CRYSTAL DISPLAY INCLUDING THE SAME”, Korean Patent Public No. 10-2011-0014904 entitled “TRANSPARENT DISPLAY DEVICE”, and Japanese Patent Publication No. 2004-333999 entitled “REFLECTION-TYPE LIQUID CRYSTAL DISPLAY”.
The transparent display devices disclosed in the above t documents require relatively high power consumption. On the other hand, low reflectivity in a reflective mode of a transparent display device makes it difficult to implement high resolution. Accordingly, there is a demand for a transparent display technology having high power efficiency in a transparent mode and providing high reflectivity in a reflective mode.